A European Union plan to set loose 3,000 balloons to mark the birth of the euro ran into a barrage of hostile questions on Monday, ranging from whether the move symbolised inflation to whether it was environmentally sound.

The colourful balloon release will be the grand finale of an EU finance ministers' meeting on New Year's Eve to announce the rates at which 11 European currencies will be converted into the new single currency.

But EU officials found the symbolic plan, heralding the January 1st launch of the euro, did not go down too well with sceptical reporters.

"I do not think you should read anything into the choice of balloons having anything to do with the monetary policy of the European Central Bank," European Commission spokesman Mr Patrick Child told a news conference, when asked if the balloons symbolised a threat of soaraway inflation in the euro zone.

Asked about a potential threat to birds, Mr Child could not say if the balloons would be made of biodegradable material or whether the plan had been cleared by the commission's environmental experts. But the commission has checked air safety regulations. Mr Child said 3,000 balloons were the most that could be released into the sky without the need to seek clearance from Belgium's air traffic control authorities.

The balloons, each bearing the euro symbol against a blue background, would be released into the sky from the courtyard of the EU's Council building where the ministers are scheduled to meet. "We thought it would be a festive and more acceptable image for the general public than pictures of the ministers meeting inside," Mr Child said.